Answer :
[tex]\begin{gathered} y=\text{ money you have to pay per month} \\ x\text{ = Mb of data} \\ FirstChoice\text{ } \\ y1=10+0.09x \\ SecondChoice \\ y2=16+0.07x \\ \\ \text{Part B} \\ 16+0.07x\text{ = }10+0.09x \\ x=300\text{ MB} \\ \end{gathered}[/tex]